build: raise minimum go version to go1.13

.github/workflows/build.yml

@@ -19,7 +19,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        job_name: ['linux', 'mac', 'windows_amd64', 'windows_386', 'other_os', 'go1.12', 'go1.13', 'go1.14', 'go1.16']
+        job_name: ['linux', 'mac', 'windows_amd64', 'windows_386', 'other_os', 'go1.13', 'go1.14', 'go1.16']
 
         include:
           - job_name: linux
@@ -69,11 +69,6 @@ jobs:
             compile_all: true
             deploy: true
 
-          - job_name: go1.12
-            os: ubuntu-latest
-            go: '1.12.x'
-            quicktest: true
-
           - job_name: go1.13
             os: ubuntu-latest
             go: '1.13.x'

docs/content/install.md

@@ -181,7 +181,7 @@ kill %1
 
 ## Install from source ##
 
-Make sure you have at least [Go](https://golang.org/) 1.12
+Make sure you have at least [Go](https://golang.org/) go1.13
 installed.  [Download go](https://golang.org/dl/) if necessary.  The
 latest release is recommended. Then
 

fs/versioncheck.go

@@ -1,7 +1,7 @@
-//+build !go1.12
+//+build !go1.13
 
 package fs
 
-// Upgrade to Go version 1.12 to compile rclone - latest stable go
+// Upgrade to Go version 1.13 to compile rclone - latest stable go
 // compiler recommended.
-func init() { Go_version_1_12_required_for_compilation() }
+func init() { Go_version_1_13_required_for_compilation() }